If you put a tagged template literal on line 42 in foo.js, every time the tagging function is called from there, the array of strings passed as the first argument is the same object. It’s unique for the source location of the template literal, so even if you paste the exact same code into bar.js, it will have a different object. So, the function can recognize that it is being called from the same location in the source. This has some interesting implications for meta programming and debugging.

I’m not sure that it matters so much to the discussion, but it is a completely unique feature, and really has to be mentioned when discussing what tagged template literals offer.

EDIT: Looked for a good reference - best detailed description I could find was here: https://exploringjs.com/es6/ch_template-literals.html#sec_im...